Embodiments of the present invention relate to the cleaning of a substrate.
In semiconductor processing, a substrate cleaning apparatus is used to clean the substrate as one step of a number of substrate processing steps. In the cleaning step, the substrate should be cleaned throughly, otherwise subsequent processing steps may be affected. A conventional substrate cleaning chamber 10, as illustrated in FIG. 1, comprises a substrate support 20 to support a substrate 50, and an upper nozzle 30a and a lower nozzle 30b, both of which are located at a sidewall of the chamber 10. In operation, as illustrated in FIG. 2, the substrate 50 is placed on the substrate support 20, and the substrate support 20 moves into the proper position. The position of the substrate 50 is between the upper nozzle 30a and lower nozzle 30b. The substrate 50 and the substrate support 20 are rotated, and during rotation, a cleaning solution 27 is injected into the chamber 10 at the substrate 50 from the upper and lower nozzles 30a, 30b. However, because the substrate 50 is rotating rapidly in the chamber 10, centrifugal forces cause the cleaning solution 27 contacting the substrate 50 to be thrown off along a tangential direction to form a cleaning solution mist in the chamber 10. The cleaning solution mist in the chamber 10 can condense on the substrate 50 to form a liquid residue 55 on the substrate surface upon completion of the cleaning process. As illustrated in FIG. 3, after leaving the chamber 10, the liquid residue 55 stains the substrate surface and may include particles and reaction residues. Such residues are undesirable because they can damage the substrate surface or cause subsequent processing steps to fail.
Thus it is desirable to have a substrate cleaning apparatus and process capable of cleaning the substrate without forming liquid residues on the substrate surface.
A substrate cleaning apparatus comprises a chamber; a substrate support capable of supporting and rotating a substrate in the chamber; a cleaning solution injector capable of injecting a cleaning solution onto the substrate in the chamber, thereby forming a cleaning gas mist in the chamber; a cleaning gas inlet capable of introducing a cleaning gas into the chamber; and an outlet capable of exhausting the cleaning gas and the cleaning gas mist.
A substrate cleaning apparatus comprises a chamber; a substrate support in the chamber, the substrate support capable of supporting a substrate and rotating the substrate in the chamber; an upper cleaning solution injector nozzle, located at a sidewall of the chamber and higher than the substrate, the injector nozzle capable of injecting a cleaning solution into the chamber; a lower cleaning solution injector nozzle, located at the sidewall of the chamber and lower than the substrate, the injector nozzle capable of injecting the cleaning solution into the chamber; a cleaning gas inlet located at a top of the chamber, the cleaning gas inlet capable of introducing a cleaning gas into the chamber; and a plurality of outlets located at the sidewall of the chamber, the cleaning gas outlets capable of exhausting from the chamber, a cleaning solution mist formed from the cleaning solution and the cleaning gas.
A substrate cleaning method comprises rotating a substrate in a chamber, spraying a cleaning solution onto the substrate, thereby forming a cleaning gas mist in the chamber; introducing a cleaning gas into the chamber; and exhausting the cleaning solution mist and cleaning gas from the chamber.
A substrate cleaning apparatus comprises a chamber; a substrate support capable of supporting and rotating a substrate in the chamber; a cleaning solution injector capable of injecting a cleaning solution onto the substrate in the chamber, thereby forming a cleaning gas mist in the chamber; means for introducing a cleaning gas into the chamber; and means for exhausting the cleaning solution mist and cleaning gas from the chamber.